// http/axios.js
import config from "@/config";
import axios from 'axios'
import {
    ElLoading,
    ElMessage
} from 'element-plus';
//创建axios的一个实例
const instance = axios.create({
    baseURL: config.api, //接口统一域名
    timeout: 6000, //设置超时
    headers: {
        'Content-Type': 'application/json;charset=UTF-8;',
    }
})
let loading,//正在请求的数量
    requestCount = 0,
    message;
//显示loading
const showLoading = () => {
    if (requestCount === 0 && !loading) {
        loading = ElLoading.service({
            text: "加载中……",
            background: 'rgba(0, 0, 0, 0.7)',
            spinner: 'el-icon-loading',
        })
    }
    requestCount++;
}
//隐藏loading
const hideLoading = () => {
    requestCount--
    if (requestCount === 0) {
        loading.close()
    }
}

//请求拦截器
instance.interceptors.request.use((config) => {
        showLoading()
        // 每次发送请求之前判断是否存在token，如果存在，则统一在http请求的header都加上token，不用每次请求都手动添加了
        const token = window.localStorage.getItem('token');
        token && (config.headers.Authorization = token)
        //若请求方式为post，则将data参数转为JSON字符串
        if (config.method === 'POST') {
            config.data = JSON.stringify(config.data);
        }
        return config;
    }, (error) => {
        // 对请求错误做些什么
        return Promise.reject(error)
    }
);

//响应拦截器
instance.interceptors.response.use((response) => {
    hideLoading()
    //响应成功
    return response.data;
}, (error) => {
    // eslint-disable-next-line
    console.log(`拦截器报错：${error}`)
    //响应错误
    if (error.response && error.response.status) {
        const status = error.response.status
        switch (status) {
            case 400:
                message = '请求错误';
                break;
            case 401:
                message = '请求错误';
                break;
            case 404:
                message = '请求地址出错';
                break;
            case 408:
                message = '请求超时';
                break;
            case 500:
                message = '服务器内部错误!';
                break;
            case 501:
                message = '服务未实现!';
                break;
            case 502:
                message = '网关错误!';
                break;
            case 503:
                message = '服务不可用!';
                break;
            case 504:
                message = '网关超时!';
                break;
            case 505:
                message = 'HTTP版本不受支持';
                break;
            default:
                message = '请求失败'
        }
        ElMessage.error(message);
        return Promise.reject(error);
    }
    hideLoading();
    return Promise.reject(error);
});


export default instance;
